High Quality Content by WIKIPEDIA articles! The Saigon River Tunnel is an underground tunnel that opened on November 20, 2011. It runs underneath the Saigon River in Ho Chi Minh City, the largest city of Vietnam. The tunnel was built with capital from the Japanese ODA, in conjunction with a consortium of Japanese contractors. The tunnel connects the existing urban center of Ho Chi Minh City with Thu Thiem New Urban Area in District 2. The Saigon River Tunnel is part of the East-West Boulevard, an important road project under construction to ease the congestion of transport in the inner city as well as transportation from downtown to the Mekong Delta Region. The existing downtown was previously only linked with the Thu Thiem New Urban Area by many bridges, namely: Thu Thiem Bridge, Phu My Bridge and Ba Son Bridge.